Printing methods used on illustrated advertising covers
By: Michael Heller

Oct 1 , 2002

Mike Heller lead our October 8th seminar on printing methods used to create illustrated
advertising covers and enclosures. He noted that during the 19th century there were basically
three methods used:

a) The best known is recess printing (colloquially referred to as engraving) used for
most classic stamps. It is recognized by the raised ink likes on the printed surfaces that can be
detected by oblique lighting or running one’s finger over the printing. Some recess printing
versions are done by photogravure, which is an etching version of recess printing.

b) The second type is relief printing usually referred to as typography. Here the
printing surface is raised (as on typewriter keys) and the background cut away. It was this
method using ‘sticks of type’ that was used for most of our books and newspapers until
fairly recent times. It was the earliest, and only, form prior to Gutenberg of typographic
printing having been used in 8th century Korea and China. Apparently Dr. Alexander
Anderson (1775-1870) first practiced it in America and his students established schools of
xylographic printing (wood engraving), as it was called, in New York, Philadelphia and

When the soft side-grain or plank side was used the wood had a tendency to
crumble, thus end-grain wood engraving became preferred. A key feature of typography is
‘ink squash’ caused by the pressure of the type upon the ink applied to it so that a bit of the
ink is forced to the edge creating a small built-up ridge along the border that can be seen
under medium magnification.

c) The third process is lithography based on the concept that oil and water do not
mix. Invented by Alois Senefelder (1771-1834) circa 1800, it involves drawing in reverse
with a greasy crayon on grained stone (black and tint work by which pictures with the
gradations of pencil or chalk can be made) or in ‘ink’ on a polished stone
(chromo-lithography) for which up to 20 or 30 stones may be required.

In matter of fact it is a form of relief printing as the stone is treated by acid leaving the grease protected areas a
trifle above the others. For stamp production, the original design is ‘transferred’ using paper
transfers to a printing stone. Offset lithography occurs when the greasy ink from the
dampened plate transfers onto a rubber blanket and then to the printed-upon paper. Cameos,
popular in the 1850s are usually a form of xylography in which the background is colored and
the positive image is white. Embossing is often used to heighten the cameo effect.

NOTE: Links to illustrated covers are shown near the bottom of this page.


  Printing Methods used on Illustrated Advertising Covers

                         Presented by Michael Heller

Overview of Printing Methods

There are essentially only three different basic types of printing methods:

Relief printing – Ink is carried on raised parts of the printing surface.

Recess printing – Ink is picked up from grooves cut into the plate.

Planographic printing – Ink is picked up from the surface of the printing plate.
Relief printing – In this method, the design on the printing base consists of raised areas, to which ink is applied. The print is created when pressure is put on the back of the paper and ink is transferred to the paper from the raised areas of the printing base.

Two forms of relief printing used in the 19th century were woodcuts and wood engraving. The woodcut technique is one of the oldest forms of relief printing, dating back to the ninth century in China and the fourteenth century in Europe. A woodcut is made using the soft side-grain or plank side of a block of wood. The design is either drawn or painted directly on the wood block or pasted on it. The area all around the design is then cut away, with the raised ridges forming the black lines of the print. Given the soft nature of the wood surface, there is a tendency for the wood to crumble after repeated use and it can be difficult to achieve fine detail in the print.

Invented in the late eighteenth century, wood engraving is a variation of the woodcut. Here, the wood is cut cross-grained rather than plankwise, with the end-grain block used to produce more intricate work. Using a tool similar to an engraver’s burin, the wood-engraver incises lines into the hard wood, rather than cutting away wood to leave lines exposed. In contrast to the woodcut method, wood engraving can produce very detailed prints. Note that, in spite of the term “engraving”, the latter method is a relief printing process.

The majority of prints found in books and newspapers of the 1800’s were produced by wood engraving. Although many of the prints were drawn on the wood itself, by the 1860s, it became common to project a photograph of an image onto the wood block, with the surface sensitized in a manner similar to a sheet of photographic paper.

Typography (or letterpress) is a form of relief printing used to produce postage stamps. Ink is applied to the raised letters in the plate and pressure is used to transfer the design to the stamp paper. Examples of typography include certain Postmaster Provisionals; a few Confederate issues (#6, 7 and 14); and most overprints on stamps.
Intaglio printing – This labor-intensive and expensive process requires an engraver to cut a design into a stone or metal base (usually copper or steel) using an engraving tool known as a burin. The deeper the cut, the wider the print. By varying the depth and width of the engraved lines, the engraver can produce what appears to be a three-dimensional print, with tonal areas.

Ink is applied to the printing base, which is then wiped, leaving the surface (the non-printing areas) clean. Ink is effectively held in the recessed areas and transferred to the damp paper by applying pressure through the back of the paper. This results in a very detailed printed design, which appears slightly raised above the surface of the paper. As the damp paper is essentially pushed into the grooves of the plate, the back of the paper may appear somewhat embossed. This process was used to prepare most U.S. postage stamps during the first 120 years.

Most engraved prints include some degree of etching. Here, the top of the plate is coated in wax, while the back is painted with varnish. The design is drawn in the wax, cutting through to the surface of the plate. The plate is then immersed in a bath of acid, which eats away the exposed portion of the metal plate, resulting in etched lines.

Photogravure – The design to be printed is first photographed through an extremely fine screen. The screen breaks up the photo into tiny dots, which are then etched (with acid) into the plate. Like intaglio engraving, the ink is lifted out of the etched areas when the paper is pressed against the plate. Unlike intaglio engraving, the ink does not appear raised relative to the surface of the paper.

Lithography is the most common form of planographic printing. This printing method relies on the chemical fact that oil and water will not mix. It first involves the drawing of a design in greasy ink on a flat surface (generally a stone or metal plate). The surface is then wetted with acid or some other ink repellent fluid, which essentially confines the printing ink to the greasy lines of the design. The ink on the printing area is then transferred to the paper by pressure. Relative to intaglio engraving, the printed design appears dull or flat.

Offset Printing (offset lithography) – Greasy ink is applied to the dampened plate and an impression is made on a rubber blanket. Paper is then pressed on the blanket, which picks up the ink. The process and results are very similar to traditional lithography.

U.S. stamps produced by lithography include: Post Office seals; the first five Confederate States general issues; and postage stamps from 1918-1920.

Cameos: One of the most desirable types of illustrated covers is the cameo illustration. As opposed to a typical illustration that shows the detail with black lines against a white background, the cameo type of illustration is reversed – the positive image is white and the background is colored. Most cameos appear to be relief printed (i.e., wood engraving). This type of illustration was widely used in the 1850s and is considered one of the classical forms of illustrated advertising.

Embossing is the raising of parts of the surface of a piece of paper, through the use of a die stamp. In this process, a design is first cut or etched into a plate. Then a second plate is made with the same design in relief (i.e., with the design raised above the printing plate). The embossed design is produced when paper is placed between these two plates and they are put together under pressure, which forces the relief part of the second plate into the recessed portions of the first. Many cameos are also found with embossed lettering and/or illustrations.

Characteristics of Printing Methods

There are two main features of the print that help determine the type of printing method used: how the ink lies and variations in the printed lines.

How the Ink Lies

Relief printing: The pressure of the raised printing surface pushes the ink into a rim around each printed surface (“ink squash”). The rim is most easily seen where a small patch of printed ink is surrounded by a large area of white. As there is greater pressure at the extreme edges of the image, the corners of a black printed frame are a good place to look for this dark rim.

Intaglio: Depending on the strength of the print, there may be a palpable depth of ink found in the darkest lines of the print. The paper on the reverse side may sometimes be felt as slightly embossed. In a good impression, the darker lines might appear as visible edges of ink.

Lithography: The ink appears flat; deposited smoothly without pressure.

Variations in Line Width

Relief: The printed lines seem to have arbitrary variations in width. The white (non-printed) lines may seem straighter than the black, printed lines. One test is to imagine anyone drawing or engraving the more oddly shaped individual black lines in a print.

Intaglio: The engraved lines are often pointed at each end and may appear to swell and diminish during their length. Lines often appear very straight, as if drawn.

Printing of Illustrated Covers

When it comes to determining the printing method used to produce a particular illustration, there is a fair amount of controversy and misunderstanding among both collectors and dealers. For example, illustrations on covers are frequently referred to as engravings or woodcuts when, in many instances, they are neither.

Part of the problem lies in semantics. When most collectors refer to engravings, they think of finely detailed prints made by the intaglio printing process, such as postage stamps and bank notes. In reality, relatively few illustrated covers and lettersheets were produced by intaglio printing, largely because of the high cost of this process.

To the left, is an example of aDecember2000page1 beautiful engraved illustrated lettersheet depicting the New York City post office (shown opposite the firm of Cheesebrough, Stearns & Co., dealer in silk goods). This illustrated circular, mailed from New York to Richmond, Virginia in 1847, is postmarked with a red New York 2 Cts. marking and a PAID cancel.

While some of the earlier illustrated lettersheets may have been printed with woodcuts, this was not a practical method for printing large quantities of illustrated matter. As the production of a woodcut involved the cutting away of material around the design to be printed, the physical limitations of the wood allowed only for a relatively simple picture with clear outlines. Repeated printings would lead to the breaking and degradation of the relief lines. As a result, wood engraving became a more popular form of printing, as it produced illustrations that were much finer in detail than the cruder woodcut. In fact, wood engraving may have been the predominant form of printing used to illustrate books, catalogs, circulars, handbills and newspapers during much of the nineteenth century.

The top two covers on the right are good examples of prints madeOctober2002page1 by wood engraving. The top cover shows an elaborate scene at the Cowing & Co. pump factory, at Seneca Falls, N.Y. The second cover, entitled “Intemperance is the Bane of Society”, shows an intricate illustration of both the perils of drinking and the virtues of intemperance. The scenes on the left side illustrate the horrors of drunkedness, including fighting, trips to the pawn broker and, as seen in the upper left corner, the ultimate end on the gallows! On the other side (the right side, of course), those who practice intemperance can look forward to a wonderful family life. The cover has a Bristol, NH datestamp and the three cent red stamp is cancelled with a PAID 3 in a circle.

The bottom cover on right is a cameo illustration for the Peoples Stove Works in New York City. This cameo is partially embossed. October2002page3Next, the covers to the left, show three more covers with cameo illustrations. All of these cameo covers are franked with a three cent 1851-57 issue. The top one shows the Neil House of Columbus, Ohio. The middle cover shows the warehouse of merchants Elder & Webb of Baltimore, MD. The bottom cover is a red cameo of the Exchange Hotel in Richmond, VA.

Invented in 1798, the lithographic process was an entirely new form of printing and was quickly put to commercial use. As a result of its low cost of production, it became a widely used process in the printing of illustrated envelopes. A good lithograph may look very much like an intaglio print and is sometimes mistakenly described as the latter in auction catalogs. The main difference between the two is that the lithographic design lies flat on the envelope while the intaglio design should show a raised effect, which can actually be felt in some instances. Careful examination under a magnifying glass may also reveal the more detailed lines of the intaglio printing.

The figure to the right shows some nice examples of illustrated covers printed by lithography.October2002page2 The top cover shows a delicate pictorial of Elgin, Illinois. The three cent stamp (#65) would indicate usage around 1861-65. The middle cover shows a lithographed illustration of the stove and iron works of Chamberlain & Co. Close examination reveals a very finely detailed print, similar to an intaglio engraving. The correct determination of the printing method is aided by the notation “Gibsons, Lith.” in very small letters at the lower left of the illustration. The three cent stamp is tied by a blue Cincinnati, Ohio datestamp. The bottom cover has a wonderful overall illustration on its back, depicting the Pittsburgh Water Cure. The picture includes a nicely detailed steamboat, a locomotive and a large fountain, among other things. The front of the cover is franked with a three-cent red stamp (#26).